But we have one anyway. The summer solstice - the beginning of astronomical summer in the northern hemisphere - takes place at 7:09 pm ET on June 20. That makes the longest day of the year north of the equator. From now until December, the days gradually get shorter, though not immediately cool.
We have told the U.S. has had the warmest spring since records began in the 19th century. Today there are heat warnings for 13 countries, with record highs in the upper 90's in New York, Boston and Washington, DC, and the heat index higher than 100 for the cities that include Philadelphia and Raleigh.
"You're talking about nearly 15 degrees above normal," said Kristin Kline, a meteorologist National Weather Service in Mount Holly, NJ
It is no coincidence that this happened on the day of solstice. Generally, the heat of the sun, trapped by the atmosphere, has the effect of lag, which is why in August in the U.S. are usually warmer than in April, despite the long days are the same.
Summer Solstice: Heat Wave Hits Watch Video
East Coast Heat Wave of 2012: Warning on U.S. 13 Watch Video
Colorado Wildfire Destroy 1 Million Hectares Watch Video
A quick reminder of what happened: the Earth rotates on its axis like the sun, tilted at an angle of 23.5 degrees relative to its orbit. Whatever the season, the axis shows the same path, with Polaris, the North Star, hovering over the North Pole.
This is the day that axis, as seen from the north, points toward the sun as much as it will throughout the year, and appears at its highest in the northern sky. So the Chicago and New York, for example, get more than 15 hours of sunshine today, compared with 9.1 hours of the winter solstice on December 21. And all things north of the Arctic Circle will get 24 hours of daylight at this time - compared with round-the-clock darkness six months from now.
Public health officials trying to remind people, as usual in those days, to keep air-conditioned building if possible, drink lots of water and avoid exertion, such as ozone builds up in the air. New York City schools remained open for 1.1 million students, although only 64 percent reported their classrooms have air conditioning.
Utilities and transit systems are also under pressure. With the heightened demand, the equipment is more likely to break the heat.
"While extreme temperatures can affect our equipment and infrastructure, we will do everything possible to avoid interruption of service," said Joseph Lhota, CEO of the New York Metropolitan Transportation Authority.
Forecasters said the heat wave will break with the current weekend. There is a cold front moving eastward, now stretches from Michigan to the central plains. Beyond that, you can at least be entertained that with summer here, the fall can not be far behind.